In the past, various vibrating screen devices have been provided for removing solid particles, such as cuttings, from a stream of drilling mud normally used in the rotary drilling of oil and gas wells. As the drilling bit drills the hole, cuttings are circulated up the wellbore to the surface and are there separated from the drilling fluid which is recirculated down the drill string, out through the drill bit, and back up the annulus between the drill string and the wall of the wellbore. To prevent the cuttings from obstructing this circulating stream of drilling mud, a shaker is provided which is a vibratory screen over which the stream of cutting-laden drilling mud is circulated as it exits the wellbore at the surface.
In the past, these screens have typically been one or more panels or sheets of mesh overlaying one another through which the stream of drilling fluid is circulated to remove the particles or cuttings. The particles or cuttings are collected and disposed of and the screened drilling fluid is then recirculated through the mud pumps and back down the drill string. The problem with this arrangement is that as the cuttings collect on the screens, they become clogged and less efficient and require periodic maintenance to remove the collected cuttings and particles from the screens.
An object of the present invention is to provide an endless belt continually moving vibrating screen through which the stream of particle or cutting-laden drilling fluid is circulated and which will catch the cuttings and also transport them to a desired location and thereby keep the screen clean and prevent the accumulation of cuttings or particles on the screen that will clog it up and require a temporary shut-down or other interruption to remove the cuttings.